1.1. Introduction to Workbench

Ansys Workbench combines access to Ansys applications with utilities that manage the product workflow.

Applications that can be accessed from Workbench include: Ansys DesignModeler and Ansys SpaceClaim Direct Modeler (for geometry creation); Ansys Meshing (for mesh generation); Ansys Fluent or CFX (for setting up and solving fluid dynamics analyses); and Ansys CFD-Post (for postprocessing the results). In Workbench, a project is composed of a group of systems. The project is driven by a schematic workflow that manages the connections between the systems. From the schematic, you can interact with workspaces that are native to Workbench, such as Design Exploration (parameters and design points), and you can launch applications that are data-integrated with Workbench (such as Ansys Fluent or CFX). Data-integrated applications have separate interfaces, but their data is part of the Workbench project and is automatically saved and shared with other applications as needed. This makes the process of creating and running a CFD simulation more streamlined and efficient.

Workbench allows you to construct projects composed of multiple dependent systems that can be updated sequentially based on a workflow defined by the project schematic. For instance, you can construct a project using two connected Fluent-based systems where the two systems share the same geometry and mesh; and the second system uses data from the first system as its initial solution data. When you have two systems connected in this way, you can modify the shared geometry once and then update the results for both systems with a single mouse click without having to open the Ansys Meshing application or Fluent. Some examples of when this is useful include: performing a reacting flow analysis starting from the solution obtained from a cold flow analysis; performing a second order analysis starting from the solution obtained from a first order analysis; and performing a transient simulation starting from the solution obtained from a steady-state analysis.

In addition, Workbench also allows you to copy systems in order to efficiently perform and compare multiple similar analyses. Workbench also provides a parametric modeling capabilities in conjunction with optimization techniques to allow you to efficiently investigate the effects of input parameters on selected output parameters.

For more information, see the following section:

1.1.1. Limitations

The following limitations are known when using Fluent in Workbench:

  • Fluent design point studies using the Remote Solve Manager may not completely update due to errors. Should this happen, you can rerun the affected design points and they will update as expected (you may have to rerun failed design points multiple times).

  • Workbench units and options are not passed to Fluent.

  • The text user interface (TUI) shortcuts, or aliases, for reading case and data files for Fluent in Workbench are disabled by design. For example, file read-case, f read-case, and f r-c can be used, however f rc cannot be used.

  • The version of Fluent used under Workbench must always be the version of Fluent that was packaged and installed with that version of Ansys Workbench. It is not possible to use previous versions of Fluent under Workbench even through a Fluent Inc. environment variable.

  • The Fluent GPU solver is not available in the Workbench environment. Refer to Using the Fluent Native GPU Solver in the Fluent User's Guide for additional information on the GPU solver.

  • Graphical user interface (GUI) journal files in Fluent 2024 R2 are not backwards compatible. That is, Workbench journal files (*.wbjn files) created in version 12.0 or version 12.1 that contain Fluent GUI commands may need to be recreated if they fail due to a change in the Fluent graphical user interface or a string used therein.

  • For older Fluent in Workbench projects (prior to version 2024 R2), when making any changes to the mesh using Ansys Meshing (for example, renaming a surface), you should first open Fluent using the Setup cell of the Fluid Flow (Fluent) analysis system in order for Fluent to be aware of the upstream mesh changes (for example, when detecting upstream zone name changes).

  • Object names must begin with either a letter or an underscore (_) and they cannot contain any slashes. Names containing a slash (/) may fail to be interpreted properly and cause errors because slashes are used to denote menus in the text user interface.

  • Adaptive time stepping is not supported.

  • Imprint surfaces are not supported.

  • Changing the meshing method to "Assembly Meshing" methods (for example, CutCell) from other meshing methods may not preserve the previously defined contact regions. Currently, the Fluent simulation workflow does not support this type of change.


Note:  Ansys Fluent only allows a period to be used as a decimal separator. If your system is set to a European locale that uses a comma separator (for example, Germany), fields that accept numeric input may accept a comma, but may ignore everything after the comma. If your system is set to a non-European locale, numeric fields will not accept a comma at all.

Ansys Workbench accepts commas as decimal delimiters. These are translated into periods when data is passed to Ansys Fluent.